Search

Pinus (Pinaceae) is the largest genus of the conifers, characterised by needle-leaves usually in fascicles of 2–5 and seed cones with highly specialised and diversified apophyses and umbos. Althoug...

The host range of a virus is defined as the number of species a virus potentially infects. The specialist virus infects one or few related species while the generalist virus infects several different species, possibly in different families. Origin of generalist viruses from their specialist nature and the expansion of the host range of the generalist virus occur with the host shift event in which the virus encounters and adapts to a new host. Host shift events have resulted in the majority of the newly emerging viral diseases. This review discusses the advantages and disadvantages of generalist over specialist viruses and the unique features of plant viruses and their hosts that result in a higher incidence of generalist viruses in plants.

MotivationNovel recombinant viruses may have important medical and evolutionary significance, as they sometimes display new traits not present in the parental strains. This is particularly concerning when the new viruses combine fragments coming from phylogenetically-distinct viral types. Here, we consider the task of screening large collections of sequences for such novel recombinants. A number of methods already exist for this task. However, these methods rely on complex models and heavy computations that are not always practical for a quick scan of a large number of sequences.ResultsWe have developed SHERPAS, a new program to detect novel recombinants and provide a first estimate of their parental composition. Our approach is based on the precomputation of a large database of “phylogenetically-informed k-mers”, an idea recently introduced in the context of phylogenetic placement in metagenomics. Our experiments show that SHERPAS is hundreds to thousands of times faster than existing software, and enables the analysis of thousands of whole genomes, or long sequencing reads, within minutes or seconds, and with limited loss of accuracy.Availability and ImplementationThe source code is freely available for download at https://github.com/phylo42/sherpasContactpardi@lirmm.fr, gllm.scholz@gmail.comSupplementary informationSupplementary Materials are available online.

European Research Council (ERC) Starting Grant 205905 (to O.O.) and Synergy Grant 856506—LIFEPLAN (to O.O. and T.R.); Spanish Ramón y Cajal Grant RYC-2014-16263 (to M.M.D.) (...), Delgado, M.D.M., Roslin, T., Tikhonov, G., Meyke, E., Lo, C., Gurarie, E., Abadonova, M., Abduraimov, O., Adrianova, O., Akimova, T., Akkiev, M., Ananin, A., Andreeva, E., Andriychuk, N., Antipin, M., Arzamascev, K., Babina, S., Babushkin, M., Bakin, O., Barabancova, A., Basilskaja, I., Belova, N., Belyaeva, N., Bespalova, T., Bisikalova, E., Bobretsovz, A., Bobrov, V., Bobrovskyi, V., Bochkareva, E., Bogdanov, G., Bolshakov, V., Bondarchuk, S., Bukharova, E., Butunina, A., Buyvolov, Y., Buyvolova, A., Bykov, Y., Chakhireva, E., Chashchina, O., Cherenkova, N., Chistjakov, S., Chuhontseva, S., Davydov, E.A., Demchenko, V., Diadicheva, E., Dobrolyubov, A., Dostoyevskaya, L., Drovnina, S., Drozdova, Z., Dubanaev, A., Dubrovsky, Y., Elsukov, S., Epova, L., Ermakova, O.S., Ermakova, O., Esengeldenova, A., Evstigneev, O., Fedchenko, I., Fedotova, V., Filatova, T., Gashev, S., Gavrilov, A., Gaydys, I., Golovcov, D., Goncharova, N., Gorbunova, E., Gordeeva, T., Grishchenko, V., Gromyko, L., Hohryakov, V., Hritankov, A., Ignatenko, E., Igosheva, S., Ivanova, U., Ivanova, N., Kalinkin, Y., Kaygorodova, E., Kazansky, F., Kiseleva, D., Knorrem, A., Kolpashikov, L., Korobov, E., Korolyova, H., Korotkikh, N., Kosenkov, G., Kossenko, S., Kotlugalyamova, E., Kozlovsky, E., Kozsheechkin, V., Kozurak, A., Kozyr, I., Krasnopevtseva, A., Krugliko, S., Kuberskaya, O., Kudryavtsev, A., Kulebyakina, E., Kulsha, Y., Kupriyanova, M., Kurbanbagamaev, M., Kutenkov, A., Kutenkova, N., Kuyantseva, N., Kuznetsov, A., Larin, E., Lebedev, P., Litvinov, K., Luzhkova, N., Mahmudov, A., Makovkina, L., Mamontov, V., Mayorova, S., Megalinskaja, I., Meydus, A., Minin, A., Mitrofanov, O., Motruk, M., Myslenkov, A., Nasonova, N., Nemtseva, N., Nesterova, I., Nezdoliy, T., Niroda, T., Novikova, T., Panicheva, D., Pavlov, A., Pavlova, K., Van, P., Podolski, S., Polikarpova, N., Tatiana Polyanskaya81, Pospelov, I., Pospelova, E., Prokhorov, I., Prokosheva, I., Puchnina, L., Putrashyk, I., Raiskaya, J., Rozhkov, Y., Rozhkova, O., Rudenko, M., Rybnikova, I., Rykova, S., Sahnevich, M., Samoylov, A., Sank, V., Sapelnikova, I., Sazonov, S., Selyunina, Z., Shalaeva, K., Shashkov, M., Shcherbakov, A., Shevchyk, V., Shubin, S., Shujskaja, E., Sibgatullin, R., Sikkilah, N., Sitnikova, E., Sivkov, A., Skok, N., Skorokhodova, S., Smirnova, E., Sokolova, G., Sopin, V., Spasovski, Y., Stepanov, S., Stratiy, V., Strekalovskaya, V., Sukhov, A., Suleymanova, G., Sultangareeva, L., Teleganova, V., Teplov, V., Teplova, V., Tertitsa, T., Timoshkin, V., Tirski, D., Tolmachev, A., Tomilin, A., Tselishcheva, L., Turgunov, M., Tyukh, Y., Van, V., Ershkova, E., Vasin, A., Vasina, A., Vekliuk, A., Vetchinnikova, L., Vinogradov, V., Volodchenko, N., Voloshina, I., Xoliqov, T., Yablonovska-Grishchenko, E., Yakovlev, V., Yakovleva, M., Yantser, O., Yarema, Y., Zahvatov, A., Zakharov, V., Zelenetskiy, N., Zheltukhin, A., Zubina, T., Kurhinen, J., Ovaskainen, O.

Pelliales is a basal lineage of the simple thalloid liverworts. Here, we describe a simple thalloid liverwort from the Middle Jurassic Xishanyao Formation of the Turpan–Hami Basin, Xinjiang Uygur Autonomous Region in northwestern China. The thalloid fossil liverwort is described as a new species: Pellites hamiensis (Pelliaceae, Pelliales). Pellites hamiensis nov. sp. resembles the extant species of Pelliaceae in having ribbon-like segments, conspicuous costae that appear as ridges on the ventral surface, rectangular cells with thickened walls adjacent to the margin, and elongated cells in the middle part of the thallus. The occurrence of P. hamiensis nov. sp. extends the fossil records of Pellites back to the Aalenian-Bajocian or Bajocian (ca. 170 Ma) and suggests that the divergence time of the Pelliaceae is no later than the Middle Jurassic.

Humans have an extraordinary ability to interact and cooperate with others. Despite the social and evolutionary significance of collaboration, research on finding its neural correlates has been limited partly due to restrictions on the simultaneous neuroimaging of more than one participant (also known as hyperscanning). Several studies have used dyadic fMRI hyperscanning to examine the interaction between two participants. However, to our knowledge, no study to date has aimed at revealing the neural correlates of social interactions using a three-person (or triadic) fMRI hyperscanning paradigm. Here, we simultaneously measured the blood-oxygenation level-dependent signal from 12 triads (n = 36 participants), while they engaged in a collaborative drawing task based on the social game of Pictionary. General linear model analysis revealed increased activation in the brain regions previously linked with the theory of mind during the collaborative phase compared to the independent phase of the task. Furthermore, using intersubject correlation analysis, we revealed increased synchronization of the right temporo‐parietal junction (R TPJ) during the collaborative phase. The increased synchrony in the R TPJ was observed to be positively associated with the overall team performance on the task. In sum, our paradigm revealed a vital role of the R TPJ among other theory-of-mind regions during a triadic collaborative drawing task.

Phenotypic plasticity can occur across generations (transgenerational plasticity) when environments experienced by the previous generations influenced offspring phenotype. The evolutionary importance of transgenerational plasticity, especially regarding within‐generational plasticity, is a currently hot topic in the plasticity framework. How long an environmental effect can persist across generations and whether multigenerational effects are cumulative are primordial—for the evolutionary significance of transgenerational plasticity—but still unresolved questions. In this study, we investigated how the grand‐parental, parental and offspring exposures to predation cues shape the predator‐induced defences of offspring in the Physa acuta snail. We expected that the offspring phenotypes result from a three‐way interaction among grand‐parental, parental and offspring environments. We exposed three generations of snails without and with predator cues according to a full factorial design and measured offspring inducible defences. We found that both grand‐parental and parental exposures to predator cues impacted offspring antipredator defences, but their effects were not cumulative and depended on the defences considered. We also highlighted that the grand‐parental environment did alter reaction norms of offspring shell thickness, demonstrating an interaction between the grand‐parental transgenerational plasticity and the within‐generational plasticity. We concluded that the effects of multigenerational exposure to predator cues resulted on complex offspring phenotypic patterns which are difficult to relate to adaptive antipredator advantages., How long an environmental effect can persist across generations and whether multigenerational effects are cumulative are primordial—for the evolutionary significance of transgenerational plasticity—but still unresolved questions. We exposed three generations of Physa acuta snails without and with predator cues according to a full factorial design and measured offspring inducible defences. We found that both grand‐parental and parental exposures to predator cues impacted offspring antipredator defences, but their effects were not cumulative and depended on the defences considered.

Epigenetic mechanisms of inheritance have come to occupy a prominent place in our understanding of living systems, primarily eukaryotes. There has been considerable and lively discussion of the possible evolutionary significance of transgenerational epigenetic inheritance. One particular type of epigenetic inheritance that has not figured much in general discussions is that based on conformational changes in proteins, where proteins with altered conformations can act as templates to propagate their own structure. An increasing number of such proteins - prions and prion-like - are being discovered. Phenotypes due to the structurally altered proteins are transmitted along with their structures. This review discusses the properties and implications of "classical" amyloid-forming prions, as well as the broader class of proteins with intrinsically disordered domains, which are proving to have fascinating properties that appear to play important roles in cell organisation and function, especially during stress responses.

Hibiscus hamabo is a semi-mangrove species with strong tolerance to salt and waterlogging stress. However, the molecular basis and mechanisms that underlie this strong adaptability to harsh environments remain poorly understood. Here, we assembled a high-quality, chromosome-level genome of this semi-mangrove plant and analyzed its transcriptome under different stress treatments to reveal regulatory responses and mechanisms. Our analyses suggested that H. hamabo has undergone two recent successive polyploidy events, a whole-genome duplication followed by a whole-genome triplication, resulting in an unusually large gene number (107 309 genes). Comparison of the H. hamabo genome with that of its close relative Hibiscus cannabinus, which has not experienced a recent WGT, indicated that genes associated with high stress resistance have been preferentially preserved in the H. hamabo genome, suggesting an underlying association between polyploidy and stronger stress resistance. Transcriptomic data indicated that genes in the roots and leaves responded differently to stress. In roots, genes that regulate ion channels involved in biosynthetic and metabolic processes responded quickly to adjust the ion concentration and provide metabolic products to protect root cells, whereas no such rapid response was observed from genes in leaves. Using co-expression networks, potential stress resistance genes were identified for use in future functional investigations. The genome sequence, along with several transcriptome datasets, provide insights into genome evolution and the mechanism of salt and waterlogging tolerance in H. hamabo, suggesting the importance of polyploidization for environmental adaptation.

Prokaryotes are hypothesized to have evolved from more primitive protocells. Unlike present-day cells, protocells are thought to have been devoid of complex molecular biological processes. They are believed to have mediated reproduction entirely by biophysical forces under favorable environmental conditions. Despite this proposition, little is known about the actual mechanism of their reproduction. To understand the reproduction process of protocells in their native habitat, here we used a top-down approach to transform bacterial cells into a primitive lipid vesicle-like state. Given that environmental conditions are thought to have played an essential role in mediating protocell reproduction, we then studied these cells under the presumed environmental conditions of Archaean Eon Earth. Even in the absence of functioning biological processes, cells in our study reproduced in a defined sequence of steps, always leading to the formation of viable daughter cells. Their reproduction mechanism can be explained by the interaction between intracellular metabolism, physicochemical properties of cell constituents, and, most importantly, environmental conditions. Given the simplicity of this reproduction mechanism and its suitability to environmental conditions of early Earth, we propose that protocells reproduced by this process. Moreover, this method of reproduction is also in tune with the earlier theoretical propositions on protocells, the results of the top- down approach of building a minimal cell, and the paleontological record of the Achaean Eon. Our study is the first to bridge the gap between non-living systems like lipid vesicles, living cells, and the paleontology of the Archaean Eon.

The phenotypes of plants can be influenced by the environmental conditions experienced by their parents. In some cases, such parental effects have been found to be adaptive, which has led to much speculation about their ecological and evolutionary significance. However, there is still much uncertainty about how common and how predictable parental environmental effects really are. We carried out a comprehensive test for parental effects of different environmental stresses in the model plant Arabidopsis thaliana. We subjected plants of three Arabidopsis genotypes to a broad range of biotic or abiotic stresses, or combinations thereof, and compared their offspring phenotypes in a common environment. The majority of environmental stresses (16 out of 24 stress treatments) caused significant parental effects, in particular on plant biomass and reproduction, with positive or negative effects ranging from −35% to +38% changes in offspring fitness. The expression of parental effects was strongly genotype-dependent, with some effects only present in some genotypes but absent, or even in the opposite direction, in others. Parental effects of multiple environmental stresses were often non-additive, and their effects can thus not be predicted from what we know about the effects of individual stresses. Intriguingly, the direction and magnitude of parental effects were unrelated to the direct effects on the parents: some stresses did not affect the parents but caused substantial effects on offspring, while for others the situation was reversed. In summary, parental environmental effects are common and often strong in A. thaliana, but they are genotype-dependent and difficult to predict.SignificanceStress experienced by plants can alter the phenotypes of their offspring. To understand the ecological and evolutionary significance of such parental effects, we must know how common and how predictable they are. In a large experiment with Arabidopsis thaliana, we show that the majority of 24 environmental stresses cause significant, and often strong, positive or negative parental effects. However, we also find that parental effects are genotype-specific and unrelated to the direct effect of individual stresses, and that multiple stresses often act in non-additive ways across generations. Thus, parental effects appear to be common and strong, but difficult to predict. Our findings have important implications for the study of plant responses to environmental change, and the design of stress experiments.

The observation and the quantification of asymmetry in biological structures are deeply investigated in geometric morphometrics. Patterns of asymmetry were explored in both living and fossil species. In living organisms, levels of directional and fluctuating asymmetry are informative about developmental processes and health status of the individuals. Paleontologists are primarily interested in asymmetric features introduced by the taphonomic process, as they may significantly alter the original shape of the biological remains, hampering the interpretation of morphological features which may have profound evolutionary significance. Here, we provide a new R tool that produces the numerical quantification of fluctuating and directional asymmetry and charts asymmetry directly on the specimens under study, allowing the visual inspection of the asymmetry pattern. We tested this show.asymmetry algorithm, written in the R language, on fossil and living cranial remains of the genus Homo. show.asymmetry proved successful in discriminating levels of asymmetry among sexes in Homo sapiens, to tell apart fossil from living Homo skulls, to map effectively taphonomic distortion directly on the fossil skulls, and to provide evidence that digital restoration obliterates natural asymmetry to unnaturally low levels. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

In 1859, C. R. Darwin highlighted the “inexplicable” absence of evidence of life prior to the beginning of the Cambrian. Given this lack of evidence and the natural rather than theological unfolding of life’s development Darwin espoused, over the following 50 years his newly minted theory was disputed. At the turn of the 19th century, beginning with the discoveries of C. D. Walcott, glimmerings of the previously “unknown and unknowable” early fossil record came to light – but Walcott’s Precambrian finds were also discounted. It was not until the breakthrough advances of the 1950’s and the identification of modern stromatolites (1956), Precambrian phytoplankton in shales (1950’s), stromatolitic microbes in cherts (1953), and terminal-Precambrian soft-bodied animal fossils (1950’s) that the field was placed on firm footing. Over the following half-century, the development and application of new analytical techniques coupled with the groundbreaking contributions of the Precambrian Paleobiology Research Group spurred the field to its international and distinctly interdisciplinary status. Significant progress has been made worldwide. Among these advances, the known fossil record has been extended sevenfold (from ∼0.5 to ∼3.5 Ga); the fossil record has been shown consistent with rRNA phylogenies (adding credence to both); and the timing and evolutionary significance of an increase of environmental oxygen (∼2.3 Ga), of eukaryotic organisms (∼2.0 Ga), and of evolution-speeding and biota-diversifying eukaryotic sexual reproduction (∼1.2 Ga) have been identified. Nevertheless, much remains to be learned. Such major unsolved problems include the absence of definitive evidence of the widely assumed life-generating “primordial soup”; the timing of the origin of oxygenic photosynthesis; the veracity of postulated changes in global photic-zone temperature from 3.5 Ga to the present; the bases of the advent of eukaryotic sexuality-requiring gametogenesis and syngamy; and the timing of origin and affinities of the small soft-bodied precursors of the Ediacaran Fauna.

SUMMARYThe Cambrian Stage 3 Chengjiang biota in South China is one of the most influential Konservat-Lagerstätten worldwide thanks to the fossilization of diverse non-biomineralizing organisms through pyritization. Despite their contributions to understanding the evolution of early animals, several Chengjiang species remain poorly known due to their scarcity and/or incomplete preservation. Here, we use micro-computed tomography to reveal in detail the ventral appendage organization of the enigmatic non-trilobite artiopod Pygmaclypeatus daziensis – one of the rarest euarthropods in Chengjiang – and explore its functional ecology and broader evolutionary significance. Pygmaclypeatus daziensis possesses a set of uniramous antennae and 14 pairs of post-antennal biramous appendages, the latter of which show an unexpectedly high degree of heteronomy based on the localized differentiation of the protopodite, endopodite and exopodite along the antero-posterior body axis. The small body size (less than 2 cm), presence of delicate spinose endites, and well-developed exopodites with multiple paddle-shaped lamellae on the appendages of P. daziensis indicate a nekto-benthic mode of life, and a scavenging/detritus feeding strategy. Pygmaclypeatus daziensis shows that appendage heteronomy is phylogenetically widespread within Artiopoda – the megadiverse clade that includes trilobites and their relatives with non-biomineralizing exoskeletons – and suggests that a single exopodite lobe with paddle-like lamellae is ancestral for this clade.Abstract FigureCover image: Morphological reconstruction of the non-trilobite artiopod Pygmaclypeatus daziensis from the early Cambrian (Stage 3) Chengjiang biota in south China. Artwork by Holly Sullivan (https://www.sulscientific.com/).

Williams’s need-threat model proposes that ostracism responses are reflexive and, because of their evolutionary significance, difficult to diminish. Alcohol is widely consumed in social contexts and for reasons of coping with social stress, and major theories of alcohol propose that intoxication disrupts cognitive appraisal of environmental threats, leading to stress relief. Surprisingly, though, no well-powered experimental research has examined the impact of alcohol intoxication on distress from social ostracism. In three studies across two independent laboratories ( N = 438), participants were randomly assigned to receive either an alcoholic or nonalcoholic (i.e., no-alcohol control or placebo) beverage and were exposed to an ostracism (or social inclusion) manipulation. Results, which emerged as remarkably consistent across all studies, indicated strong and consistent effects of ostracism on mood and needs satisfaction among both intoxicated and sober participants. Findings have important implications for ostracism theory and speak to boundary conditions for alcohol’s ability to relieve stress.

Songbirds have emerged as exceptional research subjects for helping us appreciate and understand estrogen synthesis and function in brain. In the context of recognizing the vertebrate-wide importance of brain aromatase expression, in this review we highlight where we believe studies of songbirds have provided clarification and conceptual insight. We follow by focusing on more recent studies of aromatase and neuroestrogen function in the hippocampus and the pallial auditory processing region NCM of songbirds. With perspectives drawn from this body of work, we speculate that the evolution of enhanced neural estrogen signaling, including in the mediation of social behaviors, may have given songbirds the resilience to radiate into one of the most successful vertebrate groups on the planet.

The embryological development of Ceriodaphnia reticulataDumont & Pensaert, 1983 and Scapholeberis rammneriJurine, 1820 were investigated using scanning electron microscopy. A carapace spine did not develop and there was no fusion of the first antennae. These are apparent apomorphies of DaphniaMüller, 1785, which suggests that the common ancestor of Daphniidae Straus, 1820 did not have a carapace spine during its embryological development, and its first antennae were short and separated during embryogenesis. Morphological evidence thus appears congruent with molecular interpretations showing that ScapholeberisSchoedler, 1858 is basal to other genera of Daphniidae, Ceriodaphnia being a sister taxon to Daphnia.

Geophytes, plants with buds on underground structures, are found throughout the plant tree of life. These below ground structures allow plants to inhabit highly seasonal and disturbance-prone environments across ecosystems. Past researchers have hypothesised that the bulbous, cormous and tuberous habits promote diversification, but this had yet to be tested. Using a comprehensive monocot data set of almost 13 000 taxa, we investigated the effects of the geophytic habit on diversification using both state-dependent and state-independent models. We found that geophytes exhibit increased rates of diversification relative to nongeophytes. State-dependent analyses recovered higher yet similar rates of diversification for bulbous, cormous and tuberous taxa compared with rhizomatous and nongeophytic taxa. However, the state-independent model returned no difference in rates among the different traits. Geophytism shows higher rates of diversification relative to nongeophytes but we found little support for the hypothesis that the evolution of the bulb, corm or tuber appears to provide a diversification increase relative to rhizomatous and nongeophytic taxa. Our broad-scale analysis highlights the overall evolutionary importance of the geophytic habit (i.e. belowground bud placement). However, our results also suggest that belowground morphological diversity alone cannot explain this rate increase. In order to further test the evolutionary significance of these underground structures, future studies should consider these in combination with other biotic and abiotic factors.

The postembryonic development of the turtle carapace was studied in the aquatic Еmys orbicularis and the terrestrial Тestudo graeca. Differences in the structure of the bony shell in aquatic and terrestrial turtles were shown to be associated with varying degrees of development of epidermal derivatives, namely, the thickness of the scutes and the depth of horny furrows. Sinking of the horny furrows into the dermis causes local changes in the structure of the collagen matrix, which might precondition the acceleration of the ossification. Aquatic turtles possess a relatively thin horny cover, whose derivatives are either weakly developed or altogether absent and thus make no noticeable impact on the growth dynamics of bony plates. Carapace plates of these turtles outgrow more or less evenly around the periphery, which results in uniform costals, relatively narrow and partly reduced neurals, and broad peripherals extending beyond the marginal scutes. In terrestrial turtles (Testudinidae), horny structures are much more developed and exert a considerable impact on the growth of bony elements. As a result, bony plates outgrow unevenly in the dermis, expanding fast in the zones under the horny furrows and slowly outside these zones. This determines the basic features of the testudinid carapace: alternately cuneate shape of costals, an alternation of broad octagonal and narrow tetragonal neurals, and the limitation of the growth of peripherals by pleuro-marginal furrows. The evolutionary significance of morphogenetic and constructional differences in the turtle carapace, and the association of these differences with the turtle habitats are discussed.

Horizontal gene transfer (HGT) has long been seen as a crucial process in the evolution of prokaryotic species, but until recently it was thought to have little, if any, effect on the evolution of eukaryotic life forms. Detecting and describing HGT events in eukaryotes is difficult, making this phenomenon at times controversial. However, modern advances in genomics and bioinformatics have radically altered our view of HGT in eukaryotes, especially in plants. It now appears that HGT to and from plant lineages is more common than previously suspected. Importantly, the transfer of functional nuclear genes with adaptive significance has been reported in numerous taxa. Here we review several recent studies that have found evidence of the horizontal transfer of nuclear genes, and argue that HGT has undoubtedly had profound impacts on plant evolution as a whole.

Investigation of the antennal surfaces in four species of the family Ecnomidae (Ecnomus insularis, E. maheensis, E. jethet, and E. tenellus) has revealed the presence of antennal structures including long trichoid, curved trichoid, mushroom-like pseudoplacoid, basiconic, styloconic, and chaetoid sensilla, as well as Bohm’s bristles. The mean number and diversity of the sensilla decrease toward the antenna apex. Interpopulation differences in the size and numbers of sensilla, mostly the curved trichoid ones, were observed in the widespread species Ecnomus tenellus, for the first time in insects. Quantitative differences in the composition of sensilla were found between all the studied species; these differences are probably adaptive. The evolutionary significance of the revealed divergence is discussed.

Attachment is imperative for many biological functions, such as holding position and climbing, but can be challenged by natural conditions. Adhesive toe pads and claws have evolved in multiple terrestrial lineages as important dynamic attachment mechanisms, and some clades (e.g., geckos) exhibit both features. The functional relationship of these features that comprise a complex attachment system is not well-understood, particularly within lizards (i.e., if pads and claws are redundant or multifunctional). Geckos exhibit highly adept frictional adhesive toe pads that continue to fuel biological inquiry and inspiration. However, gecko claws (the ancestral lizard clinging condition) have received little attention in terms of their functional or evolutionary significance. We assessed claw function in Thecadactylus rapicauda using assays of clinging performance and locomotor trials on different surfaces (artificial and natural) and inclines with claws intact, then partially removed. Area root mean square height (Sq), a metric of 3D surface roughness, was later quantified for all test surfaces, including acrylic, sandpaper, and two types of leaves (smooth and hairy). Maximum clinging force significantly declined on all non-acrylic surfaces after claw removal, indicating a substantial contribution to static clinging on rough and soft surfaces. With and without claws, clinging force exhibited a negative relationship with Sq. However, claw removal had relatively little impact on locomotor function on surfaces of different roughness at low inclines (≤30°). High static and dynamic safety factor estimates support these observations and demonstrate the species’ robust frictional adhesive system. However, maximum station-holding capacity significantly declined on the rough test surface after partial claw removal, showing that geckos rely on their claws to maintain purchase on rough, steeply inclined surfaces. Our results point to a context-dependent complex attachment system within geckos, in which pads dominate on relatively smooth surfaces and claws on relatively rough surfaces, but also that these features function redundantly, possibly synergistically, on surfaces that allow attachment of both the setae and the claw (as in some insects). Our study provides important novel perspectives on gecko attachment, which we hope will spur future functional studies, new evolutionary hypotheses, and biomimetic innovation, along with collaboration and integration of perspectives across disciplines.

ملخص البحث القصص النبوي الشريف دراسة دلالية کتاب صحيح القصص النبوي لأبي إسحاق الحويني أنموذجا تکمن براعة الکاتب في توظيف الأصوات والأبنية التي تحملها، والتراکيب التي تنظم فيها، مع ما تحمله الدلالة المعجمية؛ وذلک لنقل التجربة الشعورية للمتلقي؛ "لذا فإن الشاعر والأديب يلجأ إلى حرکة نشطة في المفردات, ولا يقتصر على المجازات, بل يعمد إلى عمليات من توسيع الدلالة أو تخصيصها، أو وضعها في موقع محدد عرفت أبعاده"([1]). وإن في القصص النبوي من "الثراء الدلالي, والتنوع في حقوله أسرار أسلوبية عميقة"([2]), وقد تناولت في هذا الفصل البناء الدلالي في القصص النبوي؛ وذلک من خلال معالجة الدلالة الآنية، والدلالة التطورية، وفيما يأتي تفصيل ذلک. ?إعداد الطالبة: أمل بنت مطر بن وثير العتيبي المملکة العربية السعودية ـ وزارة التعليم جامعة الطائف ـ کلية الآداب ـ قسم اللغة العربية الرقم الجامعي: (43680117) Research Summary The Prophet 's Stories The true book of the prophetic stories of Abu Ishaq al-Hawaini is a model The writer's ingenuity lies in the use of voices and buildings that carry them, and the structures in which they are organized, with the lexical significance, in order to convey the recipient's sentimental experience. "Therefore, the poet and writer resort to an active movement in vocabulary, not just metaphors, Signifying or assigning it, or placing it in a specific location whose dimensions are known ". In the prophetic narratives of "semantic richness and diversity in the fields of deep stylistic mysteries", this chapter deals with the semantic construction of the prophetic narratives through the treatment of instantaneous significance and evolutionary significance, as detailed below. Preparation of the student: Amal Bint Matar bin Wathir Al Otaibi Kingdom of Saudi Arabia Ministry of Education Taif University Faculty of Arts Department of Arabic Language University number: (43680117)

Pavlovian aversive conditioning is a fundamental form of learning helping organisms survive in their environment. Previous research has suggested that organisms are prepared to preferentially learn to fear stimuli that have posed threats to survival across evolution. Here, we examined whether enhanced Pavlovian aversive conditioning can occur to stimuli that are relevant to the organism’s concerns beyond biological and evolutionary considerations, and whether such preferential learning is modulated by inter-individual differences in affect and motivation. Seventy-two human participants performed a spatial cueing task where the goal-relevance of initially neutral stimuli was experimentally manipulated. They subsequently underwent a differential Pavlovian aversive conditioning paradigm, in which the goal-relevant and goal-irrelevant stimuli served as conditioned stimuli. Skin conductance response was recorded as an index of the conditioned response and participants’ achievement motivation was measured to examine its impact thereon. Results show that achievement motivation modulated Pavlovian aversive learning to goal-relevant vs. goal-irrelevant stimuli. Participants with high achievement motivation more readily acquired a conditioned response to goal-relevant compared with goal-irrelevant stimuli than did participants with lower achievement motivation. However, no difference was found between goal-relevant and goal-irrelevant stimuli during extinction. These findings suggest that stimuli that are detected as relevant to the organism can induce facilitated Pavlovian aversive conditioning even though they hold no inherent threat value and no biological evolutionary significance, and that the occurrence of such learning bias is critically dependent on inter-individual differences in the organism’s concerns, such as achievement motivation.

In this paper, I draw on knowledge from several disciplines to explicate the potential evolutionary significance of health effects of religiosity. I present three main observations. First, traditional methods of religious healers seldom rely on active remedies, but instead focus on lifestyle changes or spiritual healing practices that best can be described as placebo methods. Second, actual health effects of religiosity are thus mainly traceable to effects from a regulated lifestyle, social support networks, or placebo effects. Third, there are clear parallels between religious healing practices and currently identified methods that induce placebo effects. Physiological mechanisms identified to lie behind placebo effects activate the body’s own coping strategies and healing responses. In combination, lifestyle, social support networks, and placebo effects thus produce both actual and perceived health effects of religiosity. This may have played an important role in the evolution and diffusion of religion through two main pathways. First, any real positive health effects of religiosity would have provided a direct biological advantage. Second, any perceived health effects, both positive and negative, would further have provided a unique selling point for ‘religiosity’ per se. Actual and perceived health effects of religiosity may therefore have played an underestimated role during the evolution of religiosity through both biological and cultural pathways.

Cryptic species are detected at an ever‐increasing rate, mainly due to the application of molecular data. While the impact of this hidden diversity on macro‐ecology and conversation biology is widely recognized, its evolutionary significance is rarely. In recent years, it became apparent that definitions of cryptic species are too ambiguous to allow the differentiation between natural phenomena from human‐made artefacts. Hence, recently, a unifying conceptual framework has been proposed highlighting the necessity to test the degree of reduced phenotypic disparity in cryptic species. Within this reduced disparity also lies the evolutionary significance, as cryptic species can be regarded as the opposite of adaptive radiations. Specifically, studies on evolutionary stasis can substantially benefit from including these by addressing both patterns of reduced disparity and processes resulting in the lack of phenotypic evolution. In addition, this will allow connecting macro‐evolutionary and paleontological studies with micro‐evolutionary investigations of genotype‐phenotype linkage.

Many species of Primulaceae have chemical or medicinal importance, directly related to the presence of an important set of secretory structures distributed throughout the entire plant. Such structures are not only relevant in a pharmaceutical context, but also for taxonomic, systematic, and evolutionary studies within the family. Despite this, studies of the secretory structures in Primulaceae are still scarce. In this context, we aimed to identify and classify the diversity of secretory structures on the leaves of five Neotropical Primulaceae genera belonging to the Myrsinoideae and Theophrastoideae subfamilies, using light, confocal, and epifluorescence microscopy analysis. The species we studied had a diversity of secretory structures: mucilaginous and phenolic-content idioblasts, glandular trichomes, hydathodes, and secretory cavities/ducts. The development of secretory cavities and trichomes is asynchronous and begins before tissue and leaf maturation. Secretory cavities derive from a ground meristem cell and follow a schizogenous mode of development. The chemical nature of the secretion is diverse and varies according to the type of secretory structure and among species. Here, we hypothesize that both peltate glandular trichomes and secretory cavities may be considered a synapomorphy for Primulaceae. Moreover, we suggest that environmental factors have shaped the diversification of function of the secretory structures found in Primulaceae.

Aspiculate demosponges are rarely described in geological history due to the absence of spicules that are stable and resistant to degradation. One exception is the exquisite preservation of sponges without any mineralized skeletons discovered in Lagerstatten (e.g. the Burgess Shale). The Chengjiang Biota, an early example of a Burgess Shale-type biota in South China (Cambrian Series 2, Stage 3), is one of the only examples of convincing aspiculate sponges until now. Here, we describe Vauxia pregracilenta sp. nov. and V. paraleioia sp. nov., as well as two poorly preserved vauxiid specimens (Vauxia sp.) in open nomenclature, from the Chengjiang Biota. Vauxia pregracilenta has a fan-like holdfast and branches in various sizes, as well as a typical two-layered net-like skeleton, without spicules. The endosomal layer is hexagonal, while the dermal layer is sub-rectangular. Vauxia paraleioia is characterized by a two-layered subconical skeleton, with the dermal layer ornamented with vertical surface grooves. The openings of the dermal and endosomal layers of V. paraleioia are both hexagonal but of different sizes. These newly discovered Vauxia species indicate that the aspiculate sponges were diversified in the early Cambrian. Partial silicification of the fibres of aspiculate Vauxia are confirmed from the Chengjiang Biota. Thematic collection: This article is part of the Advances in the Cambrian Explosion collection available at: https://www.lyellcollection.org/cc/advances-cambrian-explosion

A key step in understanding the genetic basis of different evolutionary outcomes (e.g., adaptation) is to determine the roles played by different mutation types (e.g., SNPs, translocations and inversions). To do this we must simultaneously consider different mutation types in an evolutionary framework. Here, we propose a research framework that directly utilizes the most important characteristics of mutations, their population genetic effects, to determine their relative evolutionary significance in a given scenario. We review known population genetic effects of different mutation types and show how these may be connected to different evolutionary outcomes. We provide examples of how to implement this framework and pinpoint areas where more data, theory and synthesis are needed. Linking experimental and theoretical approaches to examine different mutation types simultaneously is a critical step towards understanding their evolutionary significance.

Adapting to the omnipresent gravitational field was a fundamental basis driving the flourishing of terrestrial plants on the Earth. Plants have evolved a remarkable capability that not only allows them to live and develop within the Earth’s gravity field, but it also enables them to use the gravity vector to guide the growth of roots and shoots, in a process known as gravitropism. Triggered by gravistimulation, plant gravitropism is a highly complex, multistep process that requires many organelles and players to function in an intricate coordinated way. Although this process has been studied for several 100 years, much remains unclear, particularly the early events that trigger the relocation of the auxin efflux carrier PIN-FORMED (PIN) proteins, which presumably leads to the asymmetrical redistribution of auxin. In the past decade, the LAZY gene family has been identified as a crucial player that ensures the proper redistribution of auxin and a normal tropic response for both roots and shoots upon gravistimulation. LAZY proteins appear to be participating in the early steps of gravity signaling, as the mutation of LAZY genes consistently leads to altered auxin redistribution in multiple plant species. The identification and characterization of the LAZY gene family have significantly advanced our understanding of plant gravitropism, and opened new frontiers of investigation into the novel molecular details of the early events of gravitropism. Here we review current knowledge of the LAZY gene family and the mechanism modulated by LAZY proteins for controlling both roots and shoots gravitropism. We also discuss the evolutionary significance and conservation of the LAZY gene family in plants.

While the evolutionary significance and source of consciousness remains controversial, fear is a state that is experienced consciously, and women’s experience of fear might be more accessible to awareness than men’s. This might be significant only in the extent to which it reflects a stronger response in the underlying fear system (see Chap. 4, Strength, below) or it might be significant because the conscious experience of fear feeds into decision-making (Loewenstein, Weber, Hsee, & Welch, 2001). Many studies have examined sex differences in the experience of fear using self-report methods: such studies might simply ask a large number of men and women to report how frequently and how intensely they experience fear. National and international surveys of this type show that women report more intense and long-lasting fear than men (Brebner, 2003; Brody & Hall, 1993; Crawford, Kippax, Onyx, Gault, & Benton, 1992; Fischer, 1993; Fischer & Manstead, 2000; Fischer, Mosquera, van Vianen, & Manstead, 2004; Gullone, 2000; McLean & Anderson, 2009). Simple surveys such as this allow data to be gathered from large samples, but the use of single-item measures can often lead to questions around validity (i.e. how well they actually reflect the real subjective experience of fear). Questionnaire measures are most effective when they are composed of multiple items that have been previously empirically validated (see Rust & Golombok, 2014 for how this can be achieved empirically).

Twelve specimens ofEumorphocystisBranson and Peck, 1940 provide the basis for new findings and a more informed assessment of whether this blastozoan (a group including eocrinoids, blastoids, diploporites, rhombiferans) constitutes the sister taxon to crinoids, as has been recently proposed. BothEumorphocystisand earliest-known crinoid feeding appendages express longitudinal canals, a demonstrable trait exclusive to these taxa. However, the specimen series studied here shows thatEumorphocystiscanals constrict proximally and travel within ambulacrals above the thecal cavity. This relationship is congruent with a documented blastozoan pattern but very unlike earliest crinoid topology. Earliest crinoid arm cavities lie fully beneath floor plates; these expand and merge directly with the main thecal coelomic cavity at thecal shoulders. Other associated anatomical features echo this contrasting comparison. Feeding appendages ofEumorphocystislack two-tiered cover plates, podial basins/pores, and lateral arm plating, all features of earliest crinoid ‘true arms.’Eumorphocystisfeeding appendages are buttressed by solid block-like plates added during ontogeny at a generative zone below floor plates, a pattern with no known parallel among crinoids.Eumorphocystisfeeding appendages express brachioles, erect extensions of floor plates, also unknown among crinoids. These several distinctions point to nonhomology of most feeding appendage anatomy, including longitudinal canals, removingEumorphocystisand other blastozoans from exclusive relationship with crinoids.Eumorphocystisfurther differs from crinoids in that thecal plates express diplopores, respiratory structures not present among crinoids, but ubiquitous among certain groups of blastozoans. Phylogenetic analysis placesEumorphocystisas a crownward blastozoan, far removed from crinoids.

Perception of pain in others is of great evolutionary significance for the development of human empathy. However, infants' sensitivity to others' painful experiences has not been investigated so far. Here, we explored the neural time course of infants' processing of others' pain by measuring event-related brain potentials (ERPs) while 6-month-old infants observed a painful tactile stimulation directed towards the eye and a neutral tactile stimulation on the eyebrow. We analyzed both the Negative Central (Nc) and the later Late Positive Potential (LPP) ERP components, indexing respectively attention allocation and cognitive evaluation of perceptual stimuli. Results showed that observing painful touch elicits a mid-latency Nc (300–500ms) over the right fronto-central site, which is greater in amplitude as compared to neutral touch. A divergent activity was also visible in the centro-parietal early (550–750ms) and late (800–1000ms) LPP, showing increased amplitudes in response to neutral compared to painful touch. The cognitive evaluation of painful stimuli, reflected by the LPP, might thus not be fully developed at 6months of age, as adults typically show a larger LPP in response to painful as compared to neutral stimuli. Overall, infants show early attentional attuning to others' pain. This early sensitivity to others' painful tactile experiences might form a prerequisite for the development of human empathy.

A considerable body of research on saccade trajectory has been carried out to gain a better understanding of cognitive processes. Deviations in a saccade trajectory could be caused by the distractor stimuli appearing during the saccade initiation. Several recent studies explored specific distractor features that make saccades curve away from distractor stimuli. They have shown that this deviation is affected not only by visual, but also by semantic saliency. However, many previous studies have focused only on the visual images with presumably evolutionary significance, such as violent scenes or frightened faces. The general purpose of this study was to understand whether more abstract semantic information, such as word meaning, could affect the saccade trajectory. In particular, the focus of our interest was saccade deviation after the presentation of emotional distractors compared to non-emotional ones. For a more detailed study, various measures of saccade trajectories were used, such as saccade deviation, overall direction and initial direction. Contrary to the previous research, our results did not match our initial hypothesis about significant changes in the saccade trajectory owing to the word meaning. The results suggest that competitive interaction of word meaning and saccade timing could be more complex than has been previously thought.

Boldness and aggressiveness are crucial behavioral traits in the field of animal personality, and both have important ecological and evolutionary significance. As swimming crabs (Portunus trituberculatus) are aggressive, their production is affected; thus, it is important to study their behavior. To assess the relationship between boldness and aggressiveness of male P. trituberculatus and the differences between their different life stages, we determined the individual differences in these two traits in juvenile and adult crabs under laboratory conditions. Based on the k-means cluster analysis, boldness of crabs is classified according to their rush to adventure, and aggressiveness of crabs is classified according to their aggressive behavior toward conspecifics. The results show that the personality classification of juvenile and adult crabs was consistent. Boldness was divided into three levels: bold, middle, and shy. Aggressiveness was divided into two levels: aggressiveness and non-aggressiveness. The personality of juveniles and adults P. trituberculatus males was significantly different; juveniles presented higher aggressiveness and lower boldness than adults. Additionally, a significant positive correlation between boldness and aggressiveness of adult crabs was verified (P = 0.001, ρ = 0.271). However, this correlation in juvenile crabs was not significant (P = 0.702, ρ = 0.042). These preliminary results indicate that the personality of P. trituberculatus males has developmental plasticity and adults have the boldness-aggressiveness behavioral syndrome.

Molecular recognition is a fundamental principle in biological systems. The olfactory detection of both food and predators via ecological relevant odorant cues are abilities of eminent evolutionary significance for many species. Pyrazines are such volatile cues, some of which act as both human-centered key food odorants (KFOs) and semiochemicals. A pyrazine-selective odorant receptor has been elusive. Here we screened 2,3,5-trimethylpyrazine, a KFO and semiochemical, and 2,5-dihydro-2,4,5-trimethylthiazoline, an innate fear-associated non-KFO, against 616 human odorant receptor variants, in a cell-based luminescence assay. OR5K1 emerged as sole responding receptor. Tested against a comprehensive collection of 178 KFOs, we newly identified 18 pyrazines and (2R/2S)-4-methoxy-2,5-dimethylfuran-3(2H)-one as agonists. Notably, OR5K1 orthologs in mouse and domesticated species displayed a human-like, potency-ranked activation pattern of pyrazines, suggesting a domestication-led co-evolution of OR5K1 and its orthologs. In summary, OR5K1 is a specialized olfactory receptor across mammals for the detection of pyrazine-based key food odors and semiochemicals.

Sequencing technologies have fuelled a rapid rise in descriptions of microbial communities associated with hosts, but what is often harder to ascertain is the evolutionary significance of these symbioses. Here, we review the role of vertical (VT), horizontal (HT), environmental acquisition and mixed modes of transmission (MMT), in the establishment of animal host–microbe associations. We then model four properties of gut microbiota proposed as key to promoting animal host–microbe relationships: modes of transmission, host reproductive mode, host mate choice and host fitness. We found that: (i) MMT led to the highest frequencies of host–microbe associations, and that some environmental acquisition or HT of microbes was required for persistent associations to form unless VT was perfect; (ii) host reproductive mode (sexual versus asexual) and host mate choice (for microbe carriers versus non-carriers) had little impact on the establishment of host–microbe associations; (iii) host mate choice did not itself lead to reproductive isolation, but could reinforce it; and (iv) changes in host fitness due to host–microbe associations had a minimal impact upon the formation of co-associations. When we introduced a second population, into which host–microbe carriers could disperse but in which environmental acquisition did not occur, highly efficient VT was required for host–microbe co-associations to persist. Our study reveals that transmission mode is of key importance in establishing host–microbe associations.

Background: Plants are easily affected by various environmental factors such as temperature, high salinity, and drought which will cause poor plant development and reduce crop yield. Transcription factors (TFs) are related to the stress resistance found in many plant species and play vital roles in the growth and development of plants. Among them, the RAV (related to ABI3/VP1) gene family, which is a plant-specific type of transcription factor containing AP2 (APETALA2) DNA binding domain and B3 DNA binding domain, is the focus in this research.Results: There more RAV genes/proteins (RAVs) were present in Gymnospermae and Angiosperm, a few RAVs in Bryophyta and Lycophyte, and no RAV gene was predicted in Chlorophyta. RAVs could be defined as three main groups, based on our phylogenetic analysis. The members of clade I included all plant stages from Chlorophyta to Angiosperm except Monocots. Clade II only contained eudicots plant species. Clade III, as a branch consisting of monocots plant species and Marchantia polymorpha, may help us explore the evolutionary relationship of RAVs between Bryophyta and Monocots. According to our results, it is shown that RAVs first appeared in bryophytes. While the vasculature continues to develop and evolve, RAV gene family also has functional differentiation and has formed new functions due to the existence of gene replication events.Conclusions: Our findings indicate that the RAVs originated from Bryophytes, and RAVs of these plant species had obvious divisions in the evolutionary tree, which revealed the evolution of RAVs. These results have guiding significance for further research.

Sequencing technologies have fueled a rapid rise in descriptions of microbial communities associated with hosts, but what is often harder to ascertain is their evolutionary significance. Here we review the existing literature on the role of vertical (VT), horizontal (HT), environmental acquisition, and mixed modes (MMT) of transmission for establishing animal host-microbe associations. We then modelled four properties of gut microbiota proposed as key to promoting animal host-microbe relationships: modes of transmission, host reproductive mode, host mate choice, and host fitness. We found: (i) MMT led to the highest frequencies of host-microbe associations, and some environmental acquisition or HT of microbes was required for persistent associations to form unless VT was perfect; (ii) host reproductive mode (sexual vs asexual) and host mate choice (for microbe carriers vs non-carriers) had little impact on the establishment of host-microbe associations; (iii) host mate choice did not itself lead to reproductive isolation, but could reinforce it; (iv) changes in host fitness due to host-microbe associations had a minimal impact upon the formation of co-associations. When we introduced a second population, into which host-microbe carriers could disperse but in which environmental acquisition did not occur, highly efficient VT was required for host-microbe co-associations to persist. Our study reveals that transmission mode is of key importance in establishing host-microbe associations.